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chemical engineering problem solving examples

Spreadsheet Problem-Solving for Chemical Engineers

chemical engineering problem solving examples

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Good news this course is being offered as an instructor-led virtual course., go to virtual course.

Spreadsheets are the chemical engineer’s tool of choice for day-to-day problem-solving; yet most chemical engineers have little formal training in their application to typical scenarios. This two-day course provides a comprehensive, hands-on overview of spreadsheet applications, focused on the needs of chemical engineers. Join expert instructor David Clough, who has taught this course over 100 times, as he provides dozens of useful tips and techniques to fill gaps in your spreadsheet knowledge.

Chemical engineering problem-solving with spreadsheets

In two days, you will implement typical chemical engineering calculations using Excel, including material and energy balances, fluid flow and heat transfer, separations, chemical reactions and flowsheets. You will learn methods for solving algebraic and differential equations associated with these scenarios. You will analyze data with spreadsheet methods, including statistical methods and model-fitting. Optimization methods for process design, scheduling and economics are also included. 

Save $795 or more when you take both this course and  CH766: Excel VBA Programming for Chemical Engineers . by registering for CH768 Spreadsheet Problem Solving and VBA Programming Combo Course .

chemical engineering problem solving examples

David E. Clough

Dr. David Clough has taught applied statistics at the undergraduate and graduate levels to chemical engineering students for the past 20 years.  At the graduate level, his students have included practicing professionals.

Dr. Clough recently retired after a 43-year career on the faculty of Chemical and Biological Engineering at the University of Colorado’s Boulder Campus.  He is still active in the Department in the Emeritus role, including the supervision of research in applied process control.  He teaches several AIChE Academy courses, both in-person and eLearning... Read more

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Learning outcomes:.

Improve your basic skills with Excel so that your work is more efficient and reliable.

Develop well-organized, well-documented spreadsheets for chemical engineering calculations that can be understood by other engineers (and ... by you a few months down the road).

Use Excel’s built-in functions for calculations and table-based operations.

Set up spreadsheet-based flowsheet calculations, including processes with recycle streams.

Carry out model-fitting calculations using regression techniques, both linear and nonlinear.

Learn targeting and case study techniques.

Set up cash flow tables for venture-guidance profitability analysis.

Who Should Attend:

Chemical engineers with basic knowledge of Excel and common spreadsheet operations. Those involved in process engineering, design and economic evaluation, research and development, and chemical engineering education will find value in this course.

Course Outline

Basic Spreadsheet Skills

Process Calculations

Dealing the Data

Numerical Problem-Solving

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The following are testimonials from people who recently took this course:

The instructor was very knowledgeable and I learned many cool tricks! I'm definitely glad I registered for this course.

The course is very good and well presented by Dr. Clough - Sr. Process Engineer

I've learned several valuable new techniques for Excel, both minor and significant. - J. Shofner

A laptop with Excel installed (preferably the latest version) is required for this course.

Find answers to questions about registration and refunds, tuition and fees, travel and lodging (for location-based courses), how eLearning courses work, how credits work, and more. 

Go to FAQs Page

Browse Course Material

A math diagram in rainbow color

chemical engineering problem solving examples

Material and Energy Balances screencasts

Screencasts are organized by textbook on the right.

Engineering calculations

Systems of Units mirror Temperature Scales mirror Density, Specific Volume, and Specific Gravity mirror Force & Weight (Units & Conversions) mirror Changing Units in an Equation mirror Unit Conversions (Practice) mirror Significant Figures mirror Molar Conversions mirror Mass and Mole Fractions (Conversions) mirror Dimensions of Differential Equations mirror Dimensional Homogeneity mirror Dimensionless Groups (Reynolds Number Example) mirror

Linear Interpolation mirror Linear Interpolation: a Graphical Explanation mirror Advanced Interpolation mirror Solving Set of Linear Equations mirror Linearization of Non-linear Equations mirror Linearize/Plot Non-Linear Equations (Excel) mirror Linearization Example (Cell Growth) (BIO) mirror Excel Solver Introduction mirror Solve a Set of Nonlinear Equations Using Solver mirror Solving a Nonlinear Equation in Excel mirror

Average Molecular Weight Derivation mirror Average Molecular Weight Calculation mirror Using Average Molecular Weight to Simplify Balance mirror Density, Mass Flow, and Volumetric Flow mirror Specific Gravity of a Mixture mirror Determining Concentrations of Streams (ppm) mirror Introduction to Pressure mirror Manometers mirror Acceleration due to Pressure mirror

Material Balances

Basis of a Calculation mirror General Balance for Material Balances mirror Introduction to Degrees of Freedom mirror Degree of Freedom Analysis on a Single Unit mirror Material Balance Problem Approach mirror Scaling a Material Balance mirror Flowchart Example mirror General Mass Balance on Single Tank mirror Performing a Material Balance on a Single Unit mirror Average Molecular Weight of Mixed Stream mirror Dry to Wet Basis mirror Liquid-Liquid Extraction Material Balance mirror Material Balance over a Crystallizer (Solubility) mirror Material Balances for a Mixing Process mirror Water Vapor Adsorber Material Balance mirror Wet to Dry Basis mirror

Transient Material Balances mirror Transient Material Balance Example mirror Transient Material Balance for a Solution mirror Transient Material Balances (Interactive Simulation) mirror

Solving Material Balances on Multiple Units mirror Designing a Flowchart mirror Multiple Unit Material Balance: Degree of Freedom Analysis mirror Degree of Freedom Analysis on Multiple Unit Process mirror Analysis of a Split Point mirror Bypass Example mirror Description of an Evaporative Crystallization Process with Recycle mirror Material Balances on a Crystallizer mirror Crystallizer Material Balance with Recycle mirror Evaporative Crystallization with Recycle (Interactive Simulation) mirror Mass Balances in Evaporative Crystallization (Interactive Simulation) mirror Example of a Purge Process mirror Multiple Unit Material Balance/Recycle - Decaf Coffee mirror Reactor with Recycle mirror

Stoichiometry mirror Reaction Stoichiometry (Interactive) mirror Extent of Reaction mirror Limiting Reagent (Interactive) Fractional Conversion mirror Fractional Conversion (Interactive) Percent Excess Air mirror Material Balances on System with Purge mirror Equilibrium mirror

Atomic Species Balances mirror Molecular Species Balances mirror Calculate Mole Fractions on Wet and Dry Basis mirror Single Reaction With Recycle mirror Recycle in a Chemical Reactor mirror Reactor With Recycle (Interactive Simulation) mirror Material Balances on System with Recycle and Purge - Spreadsheet mirror Reactor with Recycle and Purge Stream (Interactive Simulation) mirror System with Recycle and Purge - Example Problem mirror Three Methods for Balancing Reactive Processes mirror Two Reactions in a Two-Phase Reactor mirror Using Extent of Reaction for Multiple Reactions mirror Use Selectivity to Solve Reactor Mass Balances mirror

Overview of Combustion Chemistry mirror Material Balances on Complete Combustion of Methane mirror Complete and Partial Combustion of Ethane mirror Percent Excess Air (Combustion) mirror

Phase Equilibrium

Ideal Gas Properties mirror Standard Temperature and Pressure - Ideal Gas Law mirror Calculate the Specific Volume of Water Vapor using the Ideal Gas Law mirror Ideal Gas - Pressure and Volume Dependence on Temperature mirror Ideal Gas Law (Interactive Simulation) mirror Ideal Gas Law - Lung Example (BIO) mirror Ideal Gases Example Biofermentation (BIO) mirror Ideal Gas Mixture Characterization mirror Ideal Gas Mixtures Example mirror

Critical Properties of a Fluid (T and P) mirror Compressibility Factor (Z-Factor) Equation of State mirror Compressibility Factor Chart (simulation) mirror Reading Compressibility Factor Charts mirror Calculate Liquid Density of a Mixture mirror Cubic Equation of State Introduction mirror SRK Equation of State Example mirror Virial Equation of State Introduction mirror

Phase Behavior on a PV Diagram (Simulation) mirror Pressure-Volume Diagram mirror Pressure-Volume Diagram for Water (Interactive Simulation) mirror Phase Changes on a Pressure-Temperature Diagram mirror Water Phase Behavior on a Presssure-Temperature Diagram (Interactive Simulation) mirror Injecting a Liquid into an Evacuated Tank (Interactive Simulation) mirror Heat of Vaporization: Antoine's Equation mirror Heat of Vaporization: Clausius-Clapeyron mirror

How to use a Psychrometric Chart mirror Reading a Psychrometric Chart (Simulation) mirror Psychrometric Chart Examples mirror Single Condensable Species Balance mirror Relative and Absolute Humidity mirror Condense Water Vapor from Air mirror Air/Water Vapor-Liquid Equilibrium mirror

Gibbs Phase Rule mirror Lever Rule (Interactive) Lever Rule Derivation mirror Txy Diagram: Lever Rule mirror Lever Rule Example on P-x-y Diagram mirror Lever Rule Applied to the Bezene-Toluene Vapor Pressure Diagram (Simulation) mirror

Raoult's Law Explanation mirror Raoult's Law (Water as Condensable Component) mirror Raoult's Law Example mirror Multicondensable Species in VLE mirror Solving VLE Using Raoult's Law and Iterative Method Solver mirror Bubble and Dew Points for Binary Mixtures mirror Bubble and Dew Points on P-x-y and T-x-y Diagrams (Interactive Simulation) mirror Vapor Pressure of Binary Solutions (Interactive Simulation) mirror Pxy and Txy Diagrams for VLE (Simulation) mirror

Introduction to Non-Ideal Solutions mirror Phase Equilibrium: Txy Diagram mirror Using the DePriester Chart for Vapor Liquid Equilibrium (simulation) mirror Why a Solute Raises Boiling Point and Lowers Freezing Point mirror Derive Equation for Boiling Point Elevation mirror

Basic Ternary Phase Diagram (Interactive Simulation) mirror Interpolating Tie Lines on a Ternary Diagram mirror Triangular (Ternary) Phase Diagram Example mirror Using a Triangular (Ternary) Phase Diagram mirror Plotting a Ternary Phase Diagram mirror Using a Right Triangle, Ternary Phase Diagram mirror Miscibility and Distribution Coefficient mirror

Introduction to Solubility mirror Using Solubility Diagrams for Material Balances mirror Langmuir Isotherm Introduction mirror

Distillation of a Two Component Mixture Part 1 mirror Distillation of a Two Component Mixture Part 2 mirror Gas Stripping (Henry and Raoult's Laws) mirror MEB Final Part 3: How To Set Up A Problem/Distillation Column Mass Balance mirror MEB Final Part 4: Distillation Column Mass Balance (continued) mirror Single-Stage Extraction Calculations mirror

Energy Balances

Introduction to Energy mirror Heat Capacity Introduction mirror What is Enthalpy? mirror Calculating Enthalpy and Entropy Using the NIST WebBook mirror Reference States in Enthalpy Calculations mirror Choosing a Reference State (Example) mirror Hypothetical Process Paths mirror Problem Solving Approach mirror Open and Closed Systems mirror Latent Heat mirror Changes in Pressure at Constant Temperature mirror

Introduction to Steam Tables mirror Introduction to Steam Tables 2 mirror How to Use Steam Tables mirror Steam Tables: Interpolation mirror Linear Interpolation mirror Compare Steam Tables to Ideal Gas Law mirror

Properties of Liquid Water in Steam Tables mirror Water Properties from Steam Tables mirror Quality of Steam mirror Quality of Steam: Mass and Volume Fractions mirror Using the Steam Tables Spreadsheet mirror Steam Tables: Calculating Quality mirror Steam Table Example mirror Steam Tables: Constant Volume Process mirror Unsteady-State Energy Balance (Steam Tables) mirror Humidity Chart Example mirror Humidity Chart: Adiabatic Cooling mirror Calculate Physical Properties Using Humidity Charts mirror

Sensible Heat from Specific Enthalpy mirror Energy Balance on a Condenser mirror Energy Balance on a Heat Exchanger mirror Use Heat Capacity to Calculate Outlet Temperature mirror Calculate Heat Added Example mirror Throttle: Changing Gas Pressure mirror Adiabatic Compression of an Ideal Gas mirror Introduction to the Mechanical Energy Balance Equation mirror Bernoulli Equation Example mirror Determine Height of Water Using Bernoulli Equation mirror Calculate Flow Rate Using Bernoulli Equation mirror Bernoulli Equation and Pipe Flow (Interactive Simulation) mirror Energy Balance on a Single-Phase System mirror Including a Phase Change in an Energy Balance mirror Energy Balance on a Two-Component System with a Phase Change mirror Isothermal Mixing mirror Adiabatic Mixing mirror

Thermochemistry of Solutions mirror Heats of Formation mirror Heat of Reaction (from Heat of Formation) mirror How to Determine Heat of Reaction from Heat of Formation mirror Calculate Heat of Reaction at an Elevated Temperature mirror Heat of Combustion mirror Hess's Law mirror Calculating Enthalpy Changes Using Heat of Reaction Method mirror Calculating Enthalpy Changes Using Heats of Formation Method mirror Material and Energy Balances in a Reactor with Heat Exchange (Interactive Simulation) mirror Adiabatic Flame Temperature Introduction mirror Adiabatic Flame Temperature (Interactive Simulation) mirror

Adiabatic Flame Temperature mirror Calculate Adiabatic Flame Temperature mirror Adiabatic Flame Temperature Spreadsheet mirror Energy Balances with Unknown Outlet Conditions mirror Heat Removal from a Chemical Reactor mirror Energy Balance on Reaction System Using Heat of Formation mirror Energy Balance on Reaction System Using Heat of Reaction mirror Heat of Reaction Temperature Dependence (Interactive Simulation) mirror MEB Final Part 1: Dew Point of Combustion Reaction mirror MEB Final Part 2: Dew Point of Combustion Reaction (continued) mirror Steam Reformer Material and Energy Balances mirror

Screencasts sorted by textbook

chemical engineering problem solving examples

Interactive materials

chemical engineering problem solving examples

Watch screencasts that have built-in quizzes to help you retain information

Sample image for an interactive simulation of a psychrometric chart.

Determine how system behavior changes when variables are changed.

Material Balances ¶

When you want to know how things really work, study them when they’re coming apart. —William Gibson

Terminology ¶

First, let’s remind ourselves of the terminology for process variables .

Consider a process for converting chemical species, according to the reaction stoichiometry \(\ce{A + 3B -> 2C}\) .

digraph simple_process { splines = ortho; bgcolor=transparent; rankdir=LR; node [shape=box]; "i1" [style=invis]; "o1" [style=invis]; "r" [label="process", color=black]; "i1" -> "r" [label="stream 1 \n (species A and B)"]; "r" -> "o1" [label="stream 2 \n (species A and C)"]; }

Stream 1 has the following properties:

\(\dot m\) , \(\dot n\) , \(\dot V\)

\(\dot n_{A}\) , \(\dot n_{B}\) , \(\dot n_{C}\)

\(x_{A}\) , \(x_{B}\) , \(x_{C}\)

\(\rho\) , \(P\) , \(T\)

At steady state, which of those properties will be the same in stream 2 ?

Does the process matter?

First, as individuals, write down your answers. Then, discuss your answers with students around you.

Conservation laws

From Wikipedia : Conservation laws are fundamental to our understanding of the physical world, in that they describe which processes can or cannot occur in nature. In general, the total quantity of the property governed by that law remains unchanged during physical processes.

Which of these are conserved during ‘normal’ CBE processes?

total energy

total number of moles

moles of a given species

Overview of solving material balance problems ¶

Let’s begin with an overview of the approach to solving material balance problems. We’ll then cover methods for specific classes of problems.

Decision tree ¶

digraph decision_tree{ graph [size="4,6"]; bgcolor=transparent; ranksep=0.5; node [shape=box, width=1.75, height=0.6, fontname="Arial", color=darkolivegreen, penwidth="1.5"]; edge [color=black, arrowsize="0.8"]; /* create nodes for courses */ M1 [label="Material Balance"]; M2 [label="Total Balance\nIs Adequate"]; M3 [label="Species Balance(s)\nAre Needed"]; M4 [label="No Formation/\nConsumption"]; M5 [label="Formation/\nConsumption"]; M6 [label="Known\nStoichiometry"]; M7 [label="Unknown\nStoichiometry"]; {rank=same; M1} {rank=same; M2 M3} {rank=same; M4 M5} {rank=same; M6 M7} M1 -> M2 [style="solid"]; M1 -> M3 [style="solid"]; M3 -> M4 [style="solid"]; M3 -> M5 [style="solid"]; M5 -> M6 [style="solid"]; M5 -> M7 [style="solid"]; }

Thus, the following questions will lead you through that decision tree:

Is species information required, or will a total balance suffice?

If species information is required, are there formation/consumption terms?

If there are formation/consumption terms, is the reaction stoichiometry known or unknown?

The control volume ¶

First, let’s define a very useful term in CBE: the control volume .

A control volume is a volume fixed in space or moving with constant flow velocity through which the continuum (gas, liquid, or solid) flows.

It is essentially a region in space that we define to conduct a particular process analysis.

Our control volume could contain…

an entire process

a particular unit operation (heat exchanger, reactor, separator, …)

a series of unit operations or subprocesses

a small volume within a process

control volumes

It is very important to define your control volume when analyzing CBE processes.

Where can we apply material (and energy) balances? ¶

The material and energy balances (and other conservation laws) we will develop can be applied to almost any control volume.

Essentially, we can apply these balances whenever our control volume has inputs and/or outputs and we have some idea of what’s going on inside this volume.

Material balance equations ¶

In the equations below, we can think of the system as being our control volume.

In words, the fundamental mass balance equation is

In this course, we will focus primarily on systems at steady state . This means that relevant system properties do not change over time. Under these conditions, our material balance equation becomes

Consider the following process with input and output streams:

digraph generic_process { splines = ortho; rankdir=LR; bgcolor=transparent; node [shape=box]; "i1" [style=invis]; "i2" [style=invis]; "o1" [style=invis]; "o2" [style=invis]; "r" [label="process", color=black]; "i1" -> "r" [label="stream 1"]; "i2" -> "r" [label="stream 2"]; "r" -> "o1" [label="stream 3"]; "r" -> "o2" [label="stream 4"]; }

At steady state, the governing mass balance equation would be the following:

More generally, we have the following relationships.

Fundamental mass balance equation

Material balances equations for multiple species ¶

In the general case, the expression for the material balance on a species \(\ce{A}\) that is part of a mixture is

For steady-state conditions, this becomes

Expressing this steady-state relationship mathematically, we have

Mass balance equation for an individual species

\(R_{\text{formation, A}}\) = rate that species \(A\) is formed, in units of \(\si{mass/time}\)

\(R_{\text{consumption, A}}\) = rate that species \(A\) is consumed, in units of \(\si{mass/time}\)

Making use of relationships between our process variables , we can write this equation as

Note that the above equations should be written for one species at a time .

Material balances: No species formation or consumption ¶

A number or important problems in chemical and biological engineering do not include formation or consumption.

Exercise: Species mass balance with no formation or consumption

Two chemicals \(\ce{A}\) (desired) and \(\ce{B}\) (undesired) are partially separated using a chemical separator.

digraph generic_process { splines = ortho; bgcolor=transparent; rankdir=LR; node [shape=box]; "i1" [style=invis]; "o1" [style=invis]; "o2" [style=invis]; "r" [label="chemical separator", color=black]; "i1" -> "r" [label="feed stream"]; "r" -> "o1" [label="product stream"]; "r" -> "o2" [label="waste stream"]; }

The feed stream has a flow rate of \(\SI{100}{kg/hr}\) and contains \(\ce{A}\) at a mass fraction of \(0.20\) , with the balance being \(\ce{B}\) .

Furthermore, \(\SI{98}{percent}\) (by mass) of \(\ce{A}\) in the feed stream leaves in the product stream.

In the waste stream, the mass flow rate of \(\ce{B}\) is \(\SI{65}{kg/hr}\) .

What are the mass flow rates of \(\ce{B}\) in the product stream and \(\ce{A}\) in the waste stream?

Use our problem solving approach .

Guidelines for solving material balance problems involving multiple species

From pg 76 in Introduction to Chemical Engineering: Tools for Today and Tomorrow (5th Edition) :

Determine if species information is required, or if an overall mass balance will suffice. Note: Problems involving multiple species require species information.

If information on a particular species is required, write the balance for that species first. It may be that a single-species equation will provide enough information to solve the problem.

Use species mole balances rather than mass balances if the reaction stoichiometry is known.

Do not attempt to balance the total number of moles for reacting systems if the reaction changes the number of moles.

A total mass balance is frequently useful to determine a missing flow rate for systems where the densities of the input and output streams are approximately constant. The constant-density assumption is applicable to liquid systems that contain a small amount (small concentration) of a reactant or pollutant or dissolved substance such as a salt.

Words like consumed , formed , converted , reacted , produced , generated , absorbed , destroyed , and the like in the problem statement indicate that consumption or formation term are required in the material balance. Systems that include chemical reaction always require formation and/or consumption terms.

If a single species balance does not provide sufficient information to solve the problem, write additional material balances up to the total number of species. If there are still more unknowns than equations, look for additional relationships among the unknowns, such as

Given flow rates or ratios

Fractions (mass or mole) of all species in a stream must add up to \(1.0\)

Stoichiometry: if the process includes a chemical reaction.

Conversion: if it is known that a certain fraction ( \(X\) ) of reactant \(A\) is converted (or consumed) in the process, one can write that the rate of consumption of \(A\) equals that fraction of the total incoming flow rate of \(A\) .

Carry units as you work the problem. Calculation mistakes are frequently discovered as you try to work out the units.

Faculty of Engineering

Department of chemical engineering, problem-based learning (pbl).

Motivating students is an important first step in teaching and, according to Dr. Don Woods, one of McMaster’s authorities on Problem Based Learning, PBL creates motivation. This motivation could result from an intrinsic quality of problems.

Dr. Woods’ research also shows that by using PBL, students develop skills that serve them well in future learning and in the workplace.

What is PBL?

Problem-based Learning : PBL is any learning environment in which the problem drives the learning. That is, before students learn some knowledge they are given a problem. The problem is posed so that the students discover that they need to learn some new knowledge before they can solve the problem. Some example problem-based learning environments include:

Self Directed Learning

Small group, self-directed, self-assessed PBL  is a use of problem-based learning which embodies most of the principles known to improve learning. This learning environment is active, cooperative, self-assessed, provides prompt feedback, allows a better opportunity to account for personal learning preferences and is highly effective.

PBL in Chem Eng

Our use of small group, self-directed pbl.

Our experience has been with small group, self-directed, self-assessed PBL in tutorless groups. In the  chemical engineering program , we use PBL as part of two courses: one topic or problem in a junior level course; and five topics in a senior level course (Woods, 1991).

The students concurrently are taking five to seven required courses presented in the conventional format. Both PBL courses have about 30 to 50 students with one instructor. Hence, we use five to ten tutorless groups with five students per group. Before the students they have received about 50 hours of workshop style training in the processing skills.

The outcomes for the PBL activity are the Chemical Engineering subject knowledge (process safety and engineering economics), lifetime learning skills and chairperson skills. Each problem is studied for about one week.

Before the first PBL activity, the students have workshops introducing them to this PBL approach to learning and workshops on managing change. The students are required to submit journal reports frequently that make explicit their progress and activities within the PBL tutorless groups.

The elaboration is done by having three meetings: a goals meeting, a teach meeting and an elaboration/feedback meeting. Student-generated learning issues are validated by the instructor during the goals meeting. The students’ assessment of the partial PBL learning environment, as measured by the Course Perceptions Questionnaire (Knapper, 1994 and Ramsden, 1983), is d= +1 more positive than the responses from a control group of engineering students in a conventional program (N=47).

At McMaster University, the theme school program was created. This is a program for interdisciplinary learning that students from all disciplines may elect to take on overload.

Based on the research expertise at McMaster, one of the theme schools is on new materials and their impact on society. This school has five 3-credit courses, three 2-credit seminar courses and two 6-credit research internships. Enrolment is limited and by application. About 35 students were admitted in both the first and second year since it was started. Students are from English, biology, physical education, nursing chemistry, mathematics and engineering.

The 3-credit courses use the small group self-directed problem-based format. For each course has two instructors and 1 teaching assistant. The first course is sophomore level. In each 13-week course the tutorless student groups handle 2 to 3 cases or problems. Concurrently they are taking 5 to 7 required courses in their major area. Except for the nursing program, all the other courses the students take are presented in the conventional lecture format. The students have received no formal training in the processing skills before they enrolled in the theme school.

Our approach has been to develop these skills concurrently. We have five explicit, 1½ hour workshops that are given during the second semester of their sophomore year. The topics are understanding PBL and its expectations, managing change, problem solving, group skills and self-directed-interdependent small group learning.

The student evaluations of the program have identified the importance of these explicit workshops and have recommended that these be given before the students encounter their first case problem. Currently, this program does not explicitly include the development of processing skills as valued outcomes nor are these skills formally assessed. I believe that the program would be strengthened if it did.

The students are not required to do extensive journal writing. However, their written reports must demonstrate that they have synthesized information and material learned from other members of their group. Student’s assessment of the PBL learning environment in the Theme school, as measured by the Course Perceptions Questionnaire is d = +2 more positive than their assessment of their “home” departments. Their responses for their home department were consistent with the responses from a control group of students in a conventional program that has enrolment limited and is by application.

In Civil Engineering, Fred Hall uses small group, self-directed, self-assessed PBL in a junior level course; in Geography, Caroline Eyles and Fred Hall use this approach for a senior level project course.

In summary, these are examples of the use of small group self-directed PBL where tutorless groups of five to six students function effectively. The class sizes are in the range 30 to 50 with one or two instructors. The students concurrently take conventional courses. In these examples, the students work in tutorless groups of about 5 to 6 students.

Knapper, C. (1994) Instructional Development Center, Queen’s University, personal communication of the short CPQ version used in the paper D. Bertrand and C. Knapper (1993) “Contextual Influences on Student’s Approaches toLearning in Three Academic Departments”, Queens University, Kingston ON.

Ramsden, P. (1983) “The Lancaster Approaches to Studying and Course Perceptions Questionnaires: Lecturer’s Handbook,” Educational Methods Unit, Oxford Polytechnic, Oxford, OX3 0BP

Woods, D.R. (1991) “Issues in Implementation in an Otherwise Conventional Programme”, Chapter 12 in “The Challenges of Problem-based Learning” D. Boud and G. Feletti, ed., Kogan Page, London, 122-129.

PBL – Resources

One of the first videos on McMaster Problem Solving using Problem Based Learning methods.

Books to Help you with PBL

The book “ Problem-based Learning: Resources to gain the most from PBL ” – written for teachers and instructional development people to give the how to details for most issues that students and teachers encounter in implementing a PBL program. This gives nitty-gritty, how-to details. This was initially published as part of the teacher’s guide in 1994. It was expanded and revised in 1995 and sent out to about 40 educators for comments and suggestions. The book has been subsequently revised in 1996.

Table of contents for “ Problem-based Learning: Resources to gain the most from PBL ”

For students

To help our students in our own program, we wrote the book “ Problem-based Learning: how to gain the most from PBL “. To order any of these books use your favourite bookseller and request them using these ISBNs

Table of Contents for “ Problem-based Learning: How to gain the most from PBL ”

Appendix, Student Feedback Forms and Annotated index.

Prices excluding taxes and shipping and handling: for orders from Canada: C$

For teachers

The above book has been very popular with teachers. Thank you for your interest and support. However, to help teachers get an idea about PBL, sample it, implement some form of PBL, we have written a separate book for teachers that

This book we call “ Problem-based Learning: Helping your students gain the most from PBL “. It’s table of contents is:

This book was published in late 1994, revised in 1995, sent to about 40 educators for comments and is now revised (1996) and available free via the web.

Sample, browse, copy and use any of this book that you want. We would appreciate receiving comments and suggestions for improving it.

MPS Program

The McMaster Problem Solving (MPS) Program – Dr. Don Woods provides an outline of this program with many live links to lessons constructed to provide problem solving skills.

The MPS program and evaluation of its effectiveness

Mps units 1 to 18: focus on individuals solving relatively well-defined problems.

I have tried to give background, objectives, timing sheets and transparencies for the Units as I complete the documentation. You may use these in your context. I would appreciate your acknowledging the source.

MPS Units 19 to 29 (and 52): focus on interpersonal skills and group problems solving

MPS Units 30 to 57: focus on solving messy problems

Remembering Dr. Donald R. Woods

Donald Woods portrait

Condolences Received from Chemical Engineering Chairs, Colleagues and Friends on the news of Don Woods sudden passing

The whole chemical engineering community is mourning the passing away of Don Woods. Don has been a source of inspiration not only for chemical engineering professors but to educators in a wide range of disciplines across universities worldwide using his pioneering problem based solving ideas, concepts and techniques. With warm regards,

Michel Prof. Michel Perrier , ing., Ph.D., MACG, D.h.c. Directeur Département de génie chimique École Polytechnique

 This is very sad news. Don was such a wonderful, positive and enthusiastic person, and made such an impact in engineering education. Please extend our deepest sympathies to his family, and to his colleagues and friends, on behalf of the Chemical Engineering department at Queen’s.Don was an alumnus of Queen’s, and I can still remember him bounding – yes, bounding – up the stairs for his 50th reunion in 2007. One of Don’s classmates was the first woman to graduate in chemical engineering from Queen’s. One of the primary instructors at that time had been quite sexist and unwelcoming to her, and Don was still seething about it 50 years later. Don cared very much about engineering, education and people. A wonderful man.

James McLellan

Professor of Mathematics and Statistics Academic Director, Queen’s Innovation Connector

So sad to hear about Don’s sudden passing. Canada lost a pioneer and an innovator in education methods. There are very few who have contributed so much to Chemical engineering education. I have very nice memory of Don when he visited our Department several years ago. I always enjoy reading/referring his books on design and rule of thumbs. It is a great loss for all but above all for his family. My sincere condolences to Don’s family. Regards Peter

Peter Engelzos , UBC

I am very sad to her of Don’s passing. He was a great man, a great mentor and among, if not the, greatest engineering educator in Canada. Please pass our condolences to his family. On behalf of University of Calgary’s Department of Chemical and Petroleum Engineering. Best regards,

U.T. U. Sundararaj , Professor and Head Department of Chemical and Petroleum Engineering University of Calgary

Very sad news indeed. He was the Chemical Engineering educator  par excellence  not only in Canada but worldwide. My condolences to you, your Department and his family.

Dimitrios Berk , McGill University

Colleagues As you can see from the note from the Chair of McMaster Chem Eng, below, Professor Don Woods passed away this past weekend. As many of you know, Don was a Chemical Engineering Professor at McMaster who had a significant impact on engineering education. Though I didn’t know him well, I knew of him by reputation and by a few memorable talks I saw and through the work of others who worked with Don (e.g. Kim Woodhouse, now Dean at Queens). I still recall Don giving a seminar in our Department many (likely more than 15) years ago about problem-based learning. Many years before that he had taken his sabbatical and spent it like a student, attending classes in the chem eng curriculum. What a radical idea! One of his discoveries was that, though we frequently herald problem solving as a key skill that our students learn, he found that we don’t in fact teach it. This lead him to be a pioneer in problem-based learning as a way of teaching engineering. In my likely overly simplistic view, it’s about putting the problem first, then having students discover (with ‘coaching’) what principles, information, etc. you need to solve it. That’s as opposed to the more conventional approach where we teach principles and then give out problems that require the principles we just taught. Our conventional approach likely allows us to cover more material but at the expense of depth and what ‘sticks’ (i.e. becomes more intuitive) long term (less=more). Don’s findings led to significant changes in the curriculum at McMaster, with several problem-based courses. His papers, presentations and people he interacted with also impacted the engineering community well beyond McMaster. For my part, though I still teach mostly in the conventional way, I do use a problem-based approach (my version of it anyway) as well. Don also spoke of the importance of taking short ‘breaks’ from lecture about every 15 or 20 minutes to keep students engaged and he used this to great effect in his own talk…something I also try to use. His approach is also an inspiration to the potential great value of labs where we also actively think and do…and hence much value in the Unit Ops Renovation as part of our Advancement campaign. A great Canadian Engineering educator who will be missed.

Grant Allen , University of Toronto

I considered Don a true friend , We worked off and on together for 20+ years. To my surprise Don attended my Fathers Visitation a few years ago and he talked to my Sons and Daughter. When Don left, my kids came to me and said he knew what sports they were involved in and their work. They said “what a real nice guy” and that I was lucky to work with such people. He was the spokes person for my departmental retirement and wow he certainly gave me a send off. It was an honour and privileged to say we knew him. Val, Gord, Wayne, Maxine and Neil

Gordon Slater , Port Dover, Ontario

chemical engineering problem solving examples

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Chemistry LibreTexts

5.3: Stoichiometry Calculations

  Learning Objectives

A balanced chemical equation gives the identity of the reactants and the products as well as the accurate number of molecules or moles of each that are consumed or produced. Stoichiometry is a collective term for the quantitative relationships between the masses, the numbers of moles, and the numbers of particles (atoms, molecules, and ions) of the reactants and the products in a balanced chemical equation. A stoichiometric quantity is the amount of product or reactant specified by the coefficients in a balanced chemical equation. This section describes how to use the stoichiometry of a reaction to answer questions like the following: How much oxygen is needed to ensure complete combustion of a given amount of isooctane? (This information is crucial to the design of nonpolluting and efficient automobile engines.) How many grams of pure gold can be obtained from a ton of low-grade gold ore? (The answer determines whether the ore deposit is worth mining.) If an industrial plant must produce a certain number of tons of sulfuric acid per week, how much elemental sulfur must arrive by rail each week?

All these questions can be answered using the concepts of the mole, molar and formula masses, and solution concentrations, along with the coefficients in the appropriate balanced chemical equation.

Stoichiometry Problems

When carrying out a reaction in either an industrial setting or a laboratory, it is easier to work with masses of substances than with the numbers of molecules or moles. The general method for converting from the mass of any reactant or product to the mass of any other reactant or product using a balanced chemical equation is outlined in and described in the following text.

Steps in Converting between Masses of Reactant and Product

Converting amounts of substances to moles—and vice versa—is the key to all stoichiometry problems, whether the amounts are given in units of mass (grams or kilograms), weight (pounds or tons), or volume (liters or gallons).

To illustrate this procedure, consider the combustion of glucose. Glucose reacts with oxygen to produce carbon dioxide and water:

\[ C_6H_{12}O_6 (s) + 6 O_2 (g) \rightarrow 6 CO_2 (g) + 6 H_2O (l) \label{3.6.1} \]

Just before a chemistry exam, suppose a friend reminds you that glucose is the major fuel used by the human brain. You therefore decide to eat a candy bar to make sure that your brain does not run out of energy during the exam (even though there is no direct evidence that consumption of candy bars improves performance on chemistry exams). If a typical 2 oz candy bar contains the equivalent of 45.3 g of glucose and the glucose is completely converted to carbon dioxide during the exam, how many grams of carbon dioxide will you produce and exhale into the exam room?

The initial step in solving a problem of this type is to write the balanced chemical equation for the reaction. Inspection shows that it is balanced as written, so the strategy outlined above can be adapted as follows:

1. Use the molar mass of glucose (to one decimal place, 180.2 g/mol) to determine the number of moles of glucose in the candy bar:

\[ moles \, glucose = 45.3 \, g \, glucose \times {1 \, mol \, glucose \over 180.2 \, g \, glucose } = 0.251 \, mol \, glucose \nonumber \]

2. According to the balanced chemical equation, 6 mol of CO 2 is produced per mole of glucose; the mole ratio of CO 2 to glucose is therefore 6:1. The number of moles of CO 2 produced is thus

\[ moles \, CO_2 = mol \, glucose \times {6 \, mol \, CO_2 \over 1 \, mol \, glucose } \nonumber \]

\[ = 0.251 \, mol \, glucose \times {6 \, mol \, CO_2 \over 1 \, mol \, glucose } \nonumber \]

\[ = 1.51 \, mol \, CO_2 \nonumber \]

3. Use the molar mass of CO 2 (44.010 g/mol) to calculate the mass of CO 2 corresponding to 1.51 mol of CO 2 :

\[ mass\, of\, CO_2 = 1.51 \, mol \, CO_2 \times {44.010 \, g \, CO_2 \over 1 \, mol \, CO_2} = 66.5 \, g \, CO_2 \nonumber \]

These operations can be summarized as follows:

\[ 45.3 \, g \, glucose \times {1 \, mol \, glucose \over 180.2 \, g \, glucose} \times {6 \, mol \, CO_2 \over 1 \, mol \, glucose} \times {44.010 \, g \, CO_2 \over 1 \, mol \, CO_2} = 66.4 \, g \, CO_2 \nonumber \]

Discrepancies between the two values are attributed to rounding errors resulting from using stepwise calculations in steps 1–3. (Remember that you should generally carry extra significant digits through a multistep calculation to the end to avoid this!) This amount of gaseous carbon dioxide occupies an enormous volume—more than 33 L. Similar methods can be used to calculate the amount of oxygen consumed or the amount of water produced.

The balanced chemical equation was used to calculate the mass of product that is formed from a certain amount of reactant. It can also be used to determine the masses of reactants that are necessary to form a certain amount of product or, as shown in Example \(\PageIndex{1}\), the mass of one reactant that is required to consume a given mass of another reactant.

Example \(\PageIndex{1}\): The US Space Shuttle

The combustion of hydrogen with oxygen to produce gaseous water is extremely vigorous, producing one of the hottest flames known. Because so much energy is released for a given mass of hydrogen or oxygen, this reaction was used to fuel the NASA (National Aeronautics and Space Administration) space shuttles, which have recently been retired from service. NASA engineers calculated the exact amount of each reactant needed for the flight to make sure that the shuttles did not carry excess fuel into orbit. Calculate how many tons of hydrogen a space shuttle needed to carry for each 1.00 tn of oxygen (1 tn = 2000 lb).

A space shuttle taking off.

The US space shuttle Discovery during liftoff . The large cylinder in the middle contains the oxygen and hydrogen that fueled the shuttle’s main engine .

Given : reactants, products, and mass of one reactant

Asked for : mass of other reactant

We use the same general strategy for solving stoichiometric calculations as in the preceding example. Because the amount of oxygen is given in tons rather than grams, however, we also need to convert tons to units of mass in grams. Another conversion is needed at the end to report the final answer in tons.

A We first use the information given to write a balanced chemical equation. Because we know the identity of both the reactants and the product, we can write the reaction as follows:

\[ H_2 (g) + O_2 (g) \rightarrow H_2O (g) \nonumber \]

This equation is not balanced because there are two oxygen atoms on the left side and only one on the right. Assigning a coefficient of 2 to both H 2 O and H 2 gives the balanced chemical equation:

\[ 2 H_2 (g) + O_2 (g) \rightarrow 2 H_2O (g) \nonumber \]

Thus 2 mol of H 2 react with 1 mol of O 2 to produce 2 mol of H 2 O.

1. B To convert tons of oxygen to units of mass in grams, we multiply by the appropriate conversion factors:

\[ mass \, of \, O_2 = 1.00 \, tn \times { 2000 \, lb \over tn} \times {453.6 \, g \over lb} = 9.07 \times 10^5 \, g \, O_2 \nonumber \]

Using the molar mass of O 2 (32.00 g/mol, to four significant figures), we can calculate the number of moles of O 2 contained in this mass of O 2 :

\[ mol \, O_2 = 9.07 \times 10^5 \, g \, O_2 \times {1 \, mol \, O_2 \over 32.00 \, g \, O_2} = 2.83 \times 10^4 \, mol \, O_2 \nonumber \]

2. Now use the coefficients in the balanced chemical equation to obtain the number of moles of H 2 needed to react with this number of moles of O 2 :

\[ mol \, H_2 = mol \, O_2 \times {2 \, mol \, H_2 \over 1 \, mol \, O_2} \nonumber \]

\[ = 2.83 \times 10^4 \, mol \, O_2 \times {2 \, mol \, H_2 \over 1 \, mol \, O_2} = 5.66 \times 10^4 \, mol \, H_2 \nonumber \]

3. The molar mass of H 2 (2.016 g/mol) allows us to calculate the corresponding mass of H 2 :

\[mass \, of \, H_2 = 5.66 \times 10^4 \, mol \, H_2 \times {2.016 \, g \, H_2 \over mol \, H_2} = 1.14 \times 10^5 \, g \, H_2 \nonumber \]

Finally, convert the mass of H2 to the desired units (tons) by using the appropriate conversion factors:

\[ tons \, H_2 = 1.14 \times 10^5 \, g \, H_2 \times {1 \, lb \over 453.6 \, g} \times {1 \, tn \over 2000 \, lb} = 0.126 \, tn \, H_2 \nonumber \]

The space shuttle had to be designed to carry 0.126 tn of H 2 for each 1.00 tn of O 2 . Even though 2 mol of H 2 are needed to react with each mole of O 2 , the molar mass of H 2 is so much smaller than that of O 2 that only a relatively small mass of H 2 is needed compared to the mass of O 2 .

Exercise \(\PageIndex{1}\): Roasting Cinnabar

Cinnabar, (or Cinnabarite) \(HgS\) is the common ore of mercury. Because of its mercury content, cinnabar can be toxic to human beings; however, because of its red color, it has also been used since ancient times as a pigment.

A chunk of reddish cinnabar ore.

Alchemists produced elemental mercury by roasting cinnabar ore in air:

\[ HgS (s) + O_2 (g) \rightarrow Hg (l) + SO_2 (g) \nonumber \]

The volatility and toxicity of mercury make this a hazardous procedure, which likely shortened the life span of many alchemists. Given 100 g of cinnabar, how much elemental mercury can be produced from this reaction?

Calculating Moles from Volume

Quantitative calculations involving reactions in solution are carried out with masses , however, volumes of solutions of known concentration are used to determine the number of moles of reactants. Whether dealing with volumes of solutions of reactants or masses of reactants, the coefficients in the balanced chemical equation give the number of moles of each reactant needed and the number of moles of each product that can be produced. An expanded version of the flowchart for stoichiometric calculations is shown in Figure \(\PageIndex{2}\). The balanced chemical equation for the reaction and either the masses of solid reactants and products or the volumes of solutions of reactants and products can be used to determine the amounts of other species, as illustrated in the following examples.

The balanced chemical equation for a reaction and either the masses of solid reactants and products or the volumes of solutions of reactants and products can be used in stoichiometric calculations.

Example \(\PageIndex{2}\) : Extraction of Gold

Gold is extracted from its ores by treatment with an aqueous cyanide solution, which causes a reaction that forms the soluble [Au(CN) 2 ] − ion. Gold is then recovered by reduction with metallic zinc according to the following equation:

\[ Zn(s) + 2[Au(CN)_2]^-(aq) \rightarrow [Zn(CN)_4]^{2-}(aq) + 2Au(s) \nonumber \]

What mass of gold can be recovered from 400.0 L of a 3.30 × 10 −4 M solution of [Au(CN) 2 ] − ?

Given: chemical equation and molarity and volume of reactant

Asked for: mass of product

A The equation is balanced as written; proceed to the stoichiometric calculation. Figure \(\PageIndex{2}\) is adapted for this particular problem as follows:

As indicated in the strategy, start by calculating the number of moles of [Au(CN) 2 ] − present in the solution from the volume and concentration of the [Au(CN) 2 ] − solution:

\( \begin{align} moles\: [Au(CN)_2 ]^- & = V_L M_{mol/L} \\ & = 400 .0\: \cancel{L} \left( \dfrac{3 .30 \times 10^{4-}\: mol\: [Au(CN)_2 ]^-} {1\: \cancel{L}} \right) = 0 .132\: mol\: [Au(CN)_2 ]^- \end{align} \)

B Because the coefficients of gold and the [Au(CN) 2 ] − ion are the same in the balanced chemical equation, assuming that Zn(s) is present in excess, the number of moles of gold produced is the same as the number of moles of [Au(CN) 2 ] − (i.e., 0.132 mol of Au). The problem asks for the mass of gold that can be obtained, so the number of moles of gold must be converted to the corresponding mass using the molar mass of gold:

\( \begin{align} mass\: of\: Au &= (moles\: Au)(molar\: mass\: Au) \\ &= 0 .132\: \cancel{mol\: Au} \left( \dfrac{196 .97\: g\: Au} {1\: \cancel{mol\: Au}} \right) = 26 .0\: g\: Au \end{align}\)

At a 2011 market price of over $1400 per troy ounce (31.10 g), this amount of gold is worth $1170.

\( 26 .0\: \cancel{g\: Au} \times \dfrac{1\: \cancel{troy\: oz}} {31 .10\: \cancel{g}} \times \dfrac{\$1400} {1\: \cancel{troy\: oz\: Au}} = \$1170 \)

Exercise \(\PageIndex{2}\) : Lanthanum Oxalate

What mass of solid lanthanum(III) oxalate nonahydrate [La 2 (C 2 O 4 ) 3 •9H 2 O] can be obtained from 650 mL of a 0.0170 M aqueous solution of LaCl 3 by adding a stoichiometric amount of sodium oxalate?

Finding Mols and Masses of Reactants and Products Using Stoichiometric Factors (Mol Ratios): Finding Mols and Masses of Reactants and Products Using Stoichiometric Factors, YouTube(opens in new window) []

Either the masses or the volumes of solutions of reactants and products can be used to determine the amounts of other species in the balanced chemical equation. Quantitative calculations that involve the stoichiometry of reactions in solution use volumes of solutions of known concentration instead of masses of reactants or products. The coefficients in the balanced chemical equation tell how many moles of reactants are needed and how many moles of product can be produced.

What does a chemical engineer do?

Would you make a good chemical engineer? Take our career test and find your match with over 800 careers.

What is a Chemical Engineer?

Chemical engineers are sometimes called "universal engineers" because their knowledge base and abilities are so broad. These types of engineers have all the basic engineering training in mathematics and physics, as well as an in-depth mastery of chemistry and biology.

Why is this so useful? Because they can transform raw materials into useful products that we can all use, such as clothes, food, drink, and energy.

What does a Chemical Engineer do?

A chemical engineer influences various areas of technology by thinking of and designing processes for producing, transforming, and transporting materials. Before a chemical engineer brings these materials to full scale production, there is plenty of experimentation in the laboratory.

A chemical engineer in a manufacturing plant.

Many chemical engineers work in manufacturing, designing machines and plants. It is their job to ensure that the processes run smoothly and in the most economical manner possible. Oftentimes, these types of jobs have the title of process engineer . Chemical engineers are behind the creations and manufacturing of a wide range of products, such as plastics, paper, dyes, medicines, polymers, fertilizers, petrochemicals, and even many foods.

Energy and oil industries have always needed chemical engineers, but other job opportunities are growing even more. The demand for increased energy efficient and alternative energy sources is keeping chemical engineers with plenty of work to do.

Another growing field for chemical engineers is environmental engineering. Whether they are working on ways to clean up or prevent pollution, safely dispose of toxic waste, or manage a sewage treatment plant, there is no shortage of opportunities for a chemical engineer to work in environmental science. In fact, many companies hire chemical engineers to fill their positions in environmental engineering.

Careers in biotechnology and pharmaceuticals are also very abundant for chemical engineers. They are instrumental in creating and manufacturing drugs as well as medical and surgical supplies - everything from catheters to artificial kidneys or prosthetics.

Chemical engineering often overlaps with many other fields. For example, chemical engineers are needed for designing and manufacturing computer parts and other electronics, and they work closely with electronic engineers.

Nanotechnology is another growing field where chemical engineers work. This could be anything from using nanoparticles to purify contaminated groundwater, to working with DNA for gene or stem cell therapies.

These are just a few examples of what a chemical engineer can do. Chances are, if something is man-made, a chemical engineer had something to do with it.

Are you suited to be a chemical engineer?

Chemical engineers have distinct personalities . They tend to be investigative individuals, which means they’re intellectual, introspective, and inquisitive. They are curious, methodical, rational, analytical, and logical. Some of them are also realistic, meaning they’re independent, stable, persistent, genuine, practical, and thrifty.

Does this sound like you? Take our free career test to find out if chemical engineer is one of your top career matches.

What is the workplace of a Chemical Engineer like?

With so many different industries employing chemical engineers, there is a wide variety of workplace environments.

Large corporations, government entities, and small firms all need chemical engineers. However, most chemical engineers do work in larger companies as part of a team. About three-fourths of chemical engineers work in the manufacturing industries in some capacity.

Many chemical engineers must wear protective equipment, like goggles and helmets when working around large industrial manufacturing equipment. This equipment is outdoors sometimes, and may require the engineer to be in adverse weather conditions.

Other chemical engineers may spend their whole work day in the lab. Some engineers have the advantage of working in different areas, such as designing projects on the computer, testing them in the lab, and then moving on to the manufacturing phase. Seeing a project through to completion can be a very satisfying part of the career.

Frequently Asked Questions

What is the difference between a degree in chemical engineering and a degree in chemistry.

A degree in chemical engineering is appropriate for students who are interested in getting an engineering degree in chemical applications (as opposed to theoretical foundations). It focuses on certain aspects of math and physics, such as fluid dynamics, distillation, absorption, leeching and membrane separation, heat transfer, and equipment design.

The focus for a chemical engineer is the development of new materials and/or substances, and turning new ideas and discoveries into useful products and materials for humans. Graduates are able to work in entry-level positions in engineering, or can continue their education by pursuing a master's or doctoral degree.

A degree in chemistry looks at the analytical, organic, inorganic, and biochemistry side of chemistry. A chemist will focus on materials and processes, testing theories, analyzing substances, and measuring the physical properties of substances. A chemistry graduate can get a job as a research assistant in a chemistry lab, or continue on with their education by getting a master's or doctoral degree. Medical school is also an option.

Continue reading

What is the difference between a chemical engineer and a materials scientist?

Careers in biotechnology and pharmaceuticals are abundant for chemical engineers, as they are instrumental in creating and manufacturing drugs as well as medical and surgical supplies.

Chemical engineers will apply chemistry knowledge to the process of converting chemicals or raw materials into viable products for human use. They run large scale chemical reactions, and focus on processes to get molecules to react with one another at scale and with a desired process yield.

A materials scientist translates between what the chemists and physicists are working on, to what the engineering researchers are working on. They are responsible for the research, design, and development of materials, and will focus on how the physical structure of a certain material will affect the property of the material. They are essentially applied condensed matter physicists.

What is some good advice for chemical engineering students?

Get to know your professors, and develop a relationship with them so that you are comfortable enough to approach them when you need help or need questions answered. Always try to make an effort to solve a problem on your own first. If you are still struggling, take advantage of their knowledge and willingness to help.

Start building your network as early as you can. Your network can be your professors, your peers, or people you've met at extracurricular lectures, networking events, workshops, or internships.

One limitation of education is that a lot of time is spent learning theory, but very little time is spent getting experience on how things really work in the outside world. An excellent way to get experience and meet people is to seek out summer internship opportunities early on, and use your internships to build a portfolio of products/projects. Prospective employers will always view a graduate more seriously if they have had previous work experience.

Along with experience, make sure your science and math skills are well developed, as well as your writing and presentation skills. You will need to work well with teams, both at school and when employed, so patience and listening skills that are developed early on will come in handy. Having said that, you still need to be assertive, be able to get your point across in a respectable way, and be able to work on problem solving with others.

What is it like being a chemical engineer?

Chemical engineers solve problems that involve the production or use of chemicals and other products by applying the principles of chemistry. They design processes and equipment for chemical manufacturing, and test methods for manufacturing products.

Some specialize in a particular chemical process, such as polymerization, or oxidation. Others may specialize in a particular field. Each area of chemical engineering can be quite different from another, and can vary in the tasks and responsibilities involved. It's important to think about what area you can see yourself in, as well as the type of environment you can see yourself working in. The options are endless.

For instance, a chemical engineer can work in healthcare, construction, pharmaceuticals, manufacturing, petrochemicals, food processing, biotechnology, design, polymers, environmental health and safety, pulp and paper, and specialty chemicals. Their work environment can be in a lab, a plant, an office building, a construction site, or an oil and gas site. Some chemical engineers travel extensively, while others don't travel at all.

Regardless of the field or specialization you choose to work in, there is definite work satisfaction that comes from working with the processes of nature to meet the needs of humans and society.

Chemical Engineers are also known as: Chemical Process Engineer

Brought to you by CU Engineering (University of Colorado Boulder)

FREE K-12 standards-aligned STEM

curriculum for educators everywhere!

Find more at .

Hands-on Activity Solving Everyday Problems Using the Engineering Design Cycle

Grade Level: 7 (6-8)

(two 60-minutes class periods)

Additional materials are required if the optional design/build activity extension is conducted.

Group Size: 4

Activity Dependency: None

Subject Areas: Science and Technology

NGSS Performance Expectations:

NGSS Three Dimensional Triangle

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Engineering connection, learning objectives, materials list, worksheets and attachments, introduction/motivation, vocabulary/definitions, investigating questions, activity extensions, user comments & tips.

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A photograph shows a teacher’s classroom desk cluttered with many objects—papers, books, coffee cup, water bottle, pencils, pens, Kleenex box, vitamin bottle, lotion bottle, camera, awards, sunscreen bottle, stapler, paperclips, picture frame, flowers, etc.

This activity introduces students to the steps of the engineering design process. Engineers use the engineering design process when brainstorming solutions to real-life problems; they develop these solutions by testing and redesigning prototypes that work within given constraints. For example, biomedical engineers who design new pacemakers are challenged to create devices that help to control the heart while being small enough to enable patients to move around in their daily lives.

After this activity, students should be able to:

Educational Standards Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards. All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN) , a project of D2L ( In the ASN, standards are hierarchically structured: first by source; e.g. , by state; within source by type; e.g. , science or mathematics; within type by subtype, then by grade, etc .

Ngss: next generation science standards - science, international technology and engineering educators association - technology.

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State Standards

Massachusetts - science.

Each group needs:

To share with the entire class:

(Have the 19-slide Introduction to the Engineering Design Cycle Presentation , a PowerPoint® file, ready to show the class.)

Have you ever experienced a problem and wanted a solution to it? Maybe it was a broken backpack strap, a bookshelf that just kept falling over, or stuff spilling out of your closet? (Let students share some simple problems with the class). With a little bit of creativity and a good understanding of the engineering design process, you can find the solutions to many of these problems yourself!

But what is the engineering design process? (Listen to some student ideas shared with the class.) The engineering design process, or cycle, is a series of steps used by engineers to guide them as they solve problems.

(Show students the slide presentation. Refer to the notes under each slide for a suggested script and comments. The slides introduce the main steps of the engineering design process, and walk through a classroom problem—a teacher’s disorganized desk that is preventing timely return of graded papers—and how students devise a solution. It also describes the work of famous people—Katherine Johnson, Lee Anne Walters, Marc Edwards, James E. West and Jorge Odón—to illustrate successful examples of using the steps of the engineering design process.)

Now that we’ve explore the engineering design process, let’s see if we can solve a real-world problem. Marisol is a high-school student who is very excited to have their own locker. They have lots of books, assignments, papers and other items that they keep in their locker. However, Marisol is not very organized. Sometimes they are late to class because they need extra time to find things that were stuffed into their locker. What is Marisol’s problem? (Answer: Their locker is disorganized.) In your groups, you’ll read through Marisol’s situation and see how they use the engineering design process to solve it. Let’s get started!

This activity is intended as an introduction to the engineering design cycle. It is meant to be relatable to students and serve as a jumping off point for future engineering design work.

A circular diagram shows seven steps: 1) ask: identify the need & constraints, 2) research the problem, 3) imagine: develop possible solutions, 4) plan: select a promising solution, 5) create: build a prototype, 6) test and evaluate prototype, 7) improve: redesign as needed, step 1.

Engineers follow the steps of the engineering design process to guide them as they solve problems. The steps shown in Figure 1 are:

Ask: identify the need & constraints

Research the problem

Imagine: develop possible solutions

Plan: select a promising solution

Create: build a prototype

Test and evaluate prototype

Improve: redesign as needed

Some depictions of the engineering design process delineate a separate step—communication. In the Figure 1 graphic, communication is considered to be incorporated throughout the process. For this activity, we call out a final step— communicate the solution —as a concluding stage to explain to others how the solution was designed, why it is useful, and how they might benefit from it. See the diagram on slide 3.

For another introductory overview of engineering and design, see the What Is Engineering? What Is Design? lesson and/or show students the What Is Engineering? video. 

Before the Activity

With the Students

brainstorming: A team creativity activity with the purpose to generate a large number of potential solutions to a design challenge.

constraint: A limitation or restriction. For engineers, design constraints are the requirements and limitations that the final design solutions must meet. Constraints are part of identifying and defining a problem, the first stage of the engineering design cycle.

criteria: For engineers, the specifications and requirements design solutions must meet. Criteria are part of identifying and defining a problem, the first stage of the engineering design cycle.

develop : In the engineering design cycle, to create different solutions to an engineering problem.

engineering: Creating new things for the benefit of humanity and our world. Designing and building products, structures, machines and systems that solve problems. The “E” in STEM.

engineering design process: A series of steps used by engineering teams to guide them as they develop new solutions, products or systems. The process is cyclical and iterative. Also called the engineering design cycle.

evaluate: To assess something (such as a design solution) and form an idea about its merit or value (such as whether it meets project criteria and constraints).

optimize: To make the solution better after testing. Part of the engineering design cycle.

Pre-Activity Assessment

Intro Discussion: To gauge how much students already know about the activity topic and start students thinking about potential design problems in their everyday lives, facilitate a brief class discussion by asking students the following questions:

Activity Embedded Assessment

Small Group Discussions: As students work, observe their group discussions. Make sure the group leaders go through all the questions for each section, and that each group member contributes to the discussions.

Post-Activity Assessment

Marisol’s Design Process: Provide students with writing paper and have them write “Marisol’s Design Process” at the top. Direct them to clearly write out the steps that Marisol went through as they designed and completed their locker organizer design and label them according to where they fit in the engineering design cycle. For example, “Marisol had to jump back to avoid objects falling out of their locker” and they stated a desire to “wanted to find a way to organize their locker” both illustrate the “identifying the problem” step.

To make this a more hands-on activity, have students design and build their own locker organizers (or other solutions to real-life problems they identified) in tandem with the above-described activity, incorporating the following changes/additions to the process:

Engineering Design Process . 2014. TeachEngineering, Web. Accessed June 20, 2017.


Supporting program, acknowledgements.

This material is based upon work supported by the National Science Foundation CAREER award grant no. DRL 1552567 (Amy Wilson-Lopez) titled, Examining Factors that Foster Low-Income Latino Middle School Students' Engineering Design Thinking in Literacy-Infused Technology and Engineering Classrooms. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

Last modified: October 23, 2020

Chemical Engineering Jobs

David Burton / Getty Images

Are you interested in what types of engineering jobs you could get with a college degree in  chemical engineering ? There are several industries and employment options available for chemical engineers with bachelor's or master's degrees in the field.

Aerospace Engineer

Aerospace engineering is concerned with developing aircraft and spacecraft.


Engineering jobs in biotechnology apply biological processes to industry, such as in the production of pharmaceuticals, pest-resistant crops, or new types of bacteria.

Chemical Plant Technician

This job involves large scale manufacturing chemicals or monitoring equipment.

Civil Engineer

A civil engineer designs public works, such as dams, roads, and bridges. Chemical engineering comes into play selecting the proper materials for the job, among other things.

Computer Systems

Engineers working on computer systems develop computer hardware and software. Chemical engineers are good at developing new materials and processes for making them.

Electrical Engineering

Electrical engineers deal with all aspects of electronics, electricity, and magnetism. Jobs for chemical engineers relate to electrochemistry and materials.

Environmental Engineer

Jobs in environmental engineering integrate engineering with science to clean up pollution, ensure processes aren't harming the environment, and making sure clean air, water, and soil are available.

Food Industries

There are many career choices for chemical engineers in the food industry, including the development of new additives and new processes for preparing and preserving food.

Mechanical Engineer

Chemical engineering complements mechanical engineering whenever chemistry intersects with the design, manufacture, or maintenance of mechanical systems. For example, chemical engineers are important in the automotive industry, for work with batteries, tires, and engines.

Mining Engineer

Chemical engineers help design mining processes and analyze the chemical composition of materials and waste.

Nuclear Engineer

Nuclear engineering often employs chemical engineers to assess the interaction between materials at the facility, including the manufacture of radioisotopes.

Oil and Natural Gas Industry

Jobs in the oil and natural gas industry rely on chemical engineers to examine the chemical composition of the source material and products.

Paper Manufacture

Chemical engineers find jobs in the paper industry at paper plants and in the lab designing processes to make and improve products and analyze waste.

Petrochemical Engineer

Many different types of engineers work with petrochemicals . Chemical engineers are in particularly high demand because they can analyze petroleum and its products, help design chemical plants, and oversee the chemical processes in these plants.


The pharmaceutical industry employs chemical engineers to design new drugs and their production facilities and ensure plants are meeting environmental and health safety requirements,

Plant Design

This branch of engineering upscales processes to industrial scale and refines existing plants to improve their efficiency or to use different source materials.

Plastic and Polymer Manufacture

Chemical engineers develop and manufacture plastics and other polymers and use these materials in numerous products.

Technical Sales

Technical sales engineers assist colleagues and clients, offering support and advice. Chemical engineers can get jobs in many different technical fields because of their broad education and expertise.

Waste Treatment

A waste treatment engineer designs, monitors, and maintains equipment that removes contaminants from wastewater.

chemical engineering problem solving examples

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chemical engineering problem solving examples

Chemical Engineering—also referred to as process engineering—is the branch of engineering applying physical and life sciences, mathematics and economics to the production and transformation of chemicals, energy and materials. Traditionally, it consists of heat, mass and momentum transport, kinetics and reaction engineering, chemical thermodynamics, control and dynamic simulation, separation, and unit operations. Conventionally developed and applied for the petro-chemical and the heavy chemical industry, chemical engineering has rapidly evolved with applications in a multitude of fields, including climate change, environmental systems, biomedical, new materials and complex systems.

In 2003, the report “Beyond molecular frontiers: challenges for chemistry sciences and chemical engineering” mandated by the National Research Council of the American National Academies and chaired by Professors Breslow and Tirrell was released ( National Research Council, 2003 ). The study investigated the status of chemical science: where are we, how did we arrive at this state and where are we heading? It concluded that science has become increasingly interdisciplinary. It also identified a trend toward the strong integration from the molecular level to chemical engineering and “ the emergence of the intersections of the chemical science with all the natural sciences, agriculture, environmental science and medicine as well as with materials science, physics, information technology and many other fields of engineering .” A decade later, this vision has been largely realized and so-called “molecular engineering” that integrates chemical engineering with all sciences is now a reality. These rapidly expanding intersections of a wide range of areas of science with engineering are the new Frontiers in Chemical Engineering.

Frontiers in Science and Engineering are mobile, ever expanding in a non-linear and stochastic fashion. Any attempt to map the frontiers of knowledge is a difficult exercise that is usually out of date before it is published. An arguably more profitable alternative is to challenge the frontiers: to push their boundaries until some reaction occurs: whether rejection by the community or some progress follows in incremental or quantum steps.

Another approach to define the frontiers of chemical engineering is to consider the chemical reactions that have marked the development of humanity's current standards of living and the topics currently critical to ensure that acceptable standards are distributed more equitably around the globe without catastrophic impact on global climate and ecosystems. What is the most important chemical reaction that has impacted humanity? And what will be the next one? What are the most significant chemical technologies needed to ensure expansion of acceptable living standards while minimizing environmental impact?

To take just one of many possible candidates for the title of “Most Important Chemical Process,” the Haber-Bosch reaction, which produces ammonia by reacting atmospheric nitrogen with hydrogen, has allowed humanity to pass the 2 billion population barrier and reach the current global population of some 7 billion ( Smil, 1999 ; Kolbert, 2013 ). Ammonia is a key ingredient in fertilizer for good plant growth. Until the advent of the Haber-Bosh process in the 1913, agriculture operated under nitrogen-limited conditions with the cultivation of arable lands sufficient to feed only 2 billion people. Developing low cost fertilizer has enabled a new era of growth in both crop yields and human nutritional standards by escaping the limitations imposed by natural nitrogen fixation processes. An agricultural revolution has been the result.

Another example of chemical processes with wide social significance are the development of antibiotics, vaccines and immunology which have given mankind much better control over microbial pathogens, allowing longer and better human lives. Yet a third area of chemistry is our understanding of semiconductor materials and how to mass produce them with extraordinary precision that is the basis of modern microelectronics, computer science and the World Wide Web. These chemical and electronic technologies have effectively decoupled the memory/storage function of the human brain from its analytical capability, thereby liberating its powers to focus on creativity and connectivity in ways that previous generations could not imagine. Increasingly sophisticated application of mathematical principles to the phenomena of physics, chemistry and biological sciences, from the atomic level to intergalactic scales, enable us to better understand natural and anthropogenic phenomena and to either control them, or to prepare for changes which are beyond our control.

Langer and Tirrell, from MIT and Caltech respectively, have pioneered an engineering approach to biomaterials for medical application, even pushing the boundary of oncology and tissue engineering ( Langer and Tirrell, 2004 ; Karp and Langer, 2011 ; Schroeder et al., 2011 ). Bird et al. showed that molecular engineering of surface affects not only the behavior of liquid droplets with a surface at equilibrium, but also their dynamic interaction ( Bird et al., 2013 ).

When addressing industrial and practical problems, we often also challenge frontiers in chemical engineering. Chemical engineering represents both the application of science and the link between chemistry, society, and industry. Chemical engineering studies often push the boundaries of chemistry by applying model systems and equations developed with well-behaved systems to complex industrial challenges. The engineering approach rates and quantifies the relative importance of combined, antagonistic, or synergistic systems. With the aim of minimizing pitch deposition during papermaking, we recently investigated the effect of salts, shear, and pH on pitch coagulation to discover the effect of ion-specificity and non-ideal behaviors with shear ( Lee et al., 2012 ). In the development of paper diagnostics for blood typing, we quantified the bio-specific reversible coagulation of red blood cells and used adsorption, elution, filtration and chromatography to develop a practical technology. This applied study has highlighted the gap in knowledge on the dynamic interaction of antibodies and macromolecules with surfaces ( Khan et al., 2010 ; Al-Tamimi et al., 2012 ).

So what are some new frontiers to be challenged? From a multidimensional approach based on field and application they are as follows:

Reaction Engineering

• Combination of organic, inorganic and biochemical catalysis to decrease energy of activation, increase selectivity, reduce energy usage, by-products (separation) and replace toxic organic solvents and reagents based on scarce elements by reactions in aqueous or bio-based solvents using green chemical principles.

• Harnessing photosynthesis to convert solar energy and CO 2 into glucose, ligno-cellulosic polymers and their intermediates using enzymatic catalysts and/or aqueous systems.

• Understand and optimize mass transfer, energy transfer, extent, and selectivity of reactions in medicine. Applications include the selective destruction of cancer cells, bacteria, fungi, and viruses (infection) and the regulation of immunologic reactions.

• Predictive reaction engineering adjusting rate of reactant and product removal accordingly to kinetics of reaction to minimize side reactions, thereby making separation easier and more efficient.

Unit Operations and Transport Phenomena

• More selective, specific, and low energy separation processes for gas-gas and liquid-liquid systems.

• High flux and anti-fouling reverse osmosis and membrane separations.

• Improved separation of thermally sensitive chemicals having similar boiling points using fractional distillation, or other means.

• Better methods for pumping and transporting suspensions of solids in liquids- especially at high solids contents.

• Develop an engineering approach to model and regulate (control) the behavior and functionality of the human body and mental processes.

• Apply simulation and control strategies to the various hierarchies of biological systems, ranging from DNA and RNA, the cell, tissues, and organs, up to the human body to give improved quality of life to people with genetic and related disorders.

• Minimally invasive sensors to control blood pressure, blood lipid concentrations and heart rate.

• Nanotechnology for selectivity in oncology and drug delivery.

• Biotechnologies and improved biomaterials for organ regeneration.

• Low cost energy is key to improve living standards for the majority of people in less developed nations. With anthropogenic greenhouse gases causing a slow but steady global warming—an adequately proven reality—a prime challenge is to produce net energy with minimal environmental impact. Chemical engineers have a responsibility to verify and ensure that energy balances and thermodynamics are the best economically achievable. The production of chemicals from renewable source and using green chemistry is an extension of the challenge, and again chemical engineers' incumbent responsibility is to discover processes and reactions with positive thermodynamics and energy balances, then to optimize these processes by active engagement with economists, environmental scientists, and society at large.

• Cost-effective storage of solar energy (including solar energy embodied in wind and ocean currents) to enable distribution at times of peak human demand remains a critical issue. Development of reversible processes for energy storage and utilization that have rapid start-up and shut-down characteristics is therefore of prime importance.

• While rapid and controlled release of large quantities of (mainly) electrical energy is of importance in meeting society's needs, it should not be forgotten that there would be enormous benefit in capturing and storing solar energy in ways that mimic natural photosynthetic processes, so that solar energy is stored in chemical bonds, rather than as heat, or electronic charge separation. If the “artificial” photosynthetic reaction into which the solar energy is “pumped” consumes carbon dioxide, then clearly two major objectives would be achieved in a single technical advance. In this connection it is worth remembering that while the reaction of carbon monoxide with oxygen is highly exothermic, the reverse reaction, namely the thermal dissociation of carbon dioxide into carbon monoxide and oxygen, can occur at the sorts of temperatures that can be reached in a solar furnace ( Nigara and Gales, 1986 ). The remaining technological gaps are development of advanced refractory materials that can withstand the temperatures required to drive the reaction, heat exchange, and efficient separation of the reaction products. Dissolution of carbon monoxide in aqueous alkali to form alkali metal formats would seem to be a promising approach.

• Multiscale engineering: linking the nano, micro, and meso scales to the macro scale in both materials and processes will be fundamental to the great majority of challenges listed above.

• In order for nanotechnology to advance, molecular engineering using improved molecular dynamic simulations will be essential.

• Use of materials that can be reprocessed into similar products, or if not possible, into a cascade of products of lower value, with the final end-products being completely biodegradable.

• Develop materials and composites from low-energy processes by better understanding of the component structures from the atomic scale to macroscopic properties. Replacement of commodity applications of energy-intensive concrete and metals should be targeted.

Green Chemicals

• The principles of green chemistry have been well publicized ( Anastas and Warner, 1998 ). Maximum use needs to be made of renewable feedstock, utilizing all components. Because biomass has a low energy density compared to fossil carbon sources, the energy efficiencies of biomass processing require critical re-examination, including the development of smaller mobile processing plants that can be taken to the areas where biomass is available on a seasonal basis. Such a re-examination should not exclude possible social and community benefits.

• A key factor in better usage of biomass will be development of new chemical pathways that make more intelligent use of the structures of polysaccharides and lignins. In this connection, the bimolecular mechanisms by which certain insects in the families Hemiptera, and Hymenoptera can manipulate cell differentiation and tissue formation in higher plants to their advantage, by inducing the formation of galls and related, often highly ordered protective structures, made by the host plant certainly warrants detailed multidisciplinary study.

• While a number of useful enzymes are now produced, isolated and used on an industrial scale, the rates at which they catalyze processes are usually limited by thermal instability and denaturation by surfactants and movement of pH outside the neutral range. Chemical engineers have traditionally used heat, pressure, and pH to accelerate chemical reactions, yet the study of the molecular biology of extremophile organisms and their enzymes that have obviously evolved to withstand extreme temperatures, pressures and pH ranges that occur in deep ocean vents and volcanic pools appears to be in its infancy.

Progress in chemical engineering has often been incremental. Initially born of a marriage between mechanical engineering and applied chemistry, chemical engineering has grown into a fully-fledged broad discipline that is constantly seeking new challenges. One area in which many of these challenges are focused improved technologies to harness matter and energy in ways that generate new products, such as organs, energy storage systems, molecularly engineered composites, etc. A closely related area is process optimization to ensure that both existing and new products are manufactured in the most efficient and sustainable ways—in terms of energy and by-products. A third area of challenges is building new facilities and modifying older ones such that they have a clear social license to operate and use the technologies on which society relies to provide acceptable standards of living.

Many of the most interesting and fruitful challenges at the frontiers of chemical engineering involve the integration of chemical engineering with chemistry, physics and biology accompanied by a redefinition of the control volume. In the spirit of this philosophy, the first research topic of Frontiers in Chemical Engineering will be application of chemical engineering principles to oncology with a nanotechnology focus.

Conflict of Interest Statement

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Many thanks to the reviewer for stimulating and constructive discussion.

Al-Tamimi, M., Shen, W., Rania, Z., Huy, T., and Garnier, G. (2012). Validation of paper-based assay for rapid blood typing. Anal. Chem . 84, 1661–1668. doi: 10.1021/ac202948t

Pubmed Abstract | Pubmed Full Text | CrossRef Full Text

Anastas, P. T., and Warner, J. C. (1998). Green Chemistry: Theory and Practice . New York, NY: Oxford University Press.

Bird, J. C., Dhiman, R., Kwong, H.-M., and Varanasi, K. K. (2013). Reducing contact time of a bouncing drop. Nature 503, 385–388. doi: 10.1038/nature12740

Karp, J. M., and Langer, R. (2011). Dry solution to a sticky problem. Nature 477, 42–43. doi: 10.1038/477042a

Khan, M. S., Thouas, G., Whyte, G., Shen, W., and Garnier, G. (2010). Paper diagnostic for instantaneous blood typing. Anal. Chem . 82, 4158–4164. doi: 10.1021/ac100341n

Kolbert, E. (2013). Fertilizer, fertility and the clash over population growth. The New Yorker 89.33: 96.

Langer, R., and Tirrell, D. A. (2004). Designing materials for biology and medicine. Nature 428, 487–492. doi: 10.1038/nature02388

Lee, R., Lewis, T., Richardson, D., Stack, L. K., and Garnier, G. (2012). Effect of shear, temperature and pH on the dynamics of salt induced coagulation of wood resin colloids. Colloids Surf. A , 396, 106–114. doi: 10.1016/j.colsurfa.2011.12.049

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National Research Council. (2003). Beyond molecular frontiers: challenged for chemistry sciences and chemical engineering . Washington, DC: The National Academies Press.

Nigara, Y., and Gales, B. (1986). Production of carbon monoxide by direct thermal splitting of carbon dioxide at high temperature. Bull. Chem. Soc. Jpn . 59, 1997–2002. doi: 10.1246/bcsj.59.1997

Schroeder, A., Heller, D. A., Winslow, M. M., Dahlman, J. E., Pratt, G. W., Langer, R., et al. (2011). Treating metastatic cancer with nanotechnology. Nat. Rev. Cancer 12, 39–50. doi: 10.1038/nrc3180

Smil, V. (1999). Detonator of the population explosion. Nature 400, 415. doi: 10.1038/22672

Keywords: grand challenges, chemical engineering, materials and nanotechnology, biomedicine, energy metabolism, green chemistry technology, separation

Citation: Garnier G (2014) Grand challenges in chemical engineering. Front. Chem . 2 :17. doi: 10.3389/fchem.2014.00017

Received: 03 March 2014; Accepted: 24 March 2014; Published online: 09 April 2014.

Reviewed by:

Copyright © 2014 Garnier. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: [email protected]

MATLAB and Simulink Based Books

Chemical Engineering Computation with MATLAB, 2nd edition

Chemical Engineering Computation with MATLAB, 2nd edition continues to present basic to advanced levels of problem-solving techniques using MATLAB as the computation environment. This edition provides even more examples and problems extracted from core chemical engineering subject areas and all code is updated to MATLAB version 2020. It also includes a new chapter on computational intelligence and:

This essential textbook readies engineering students, researchers, and professionals to be proficient in the use of MATLAB to solve sophisticated real-world problems within the interdisciplinary field of chemical engineering. The text features a solutions manual, lecture slides, and MATLAB program files.

About This Book

Chemical Engineering Computation with MATLAB, 2nd edition

Yeong Koo Yeo , Hanyang University

CRC Press, Inc. , 2021

ISBN: 9780367547820 Language: English

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chemical engineering problem solving examples

How to solve difficult chemical engineering problems with quantum computing

Leading quantum chemist and a manager in the IBM Quantum Computational Science group, Gavin Jones sits down to discuss how quantum computers could be used to solve some of the most difficult questions in chemistry.

Gavin Jones on quantum computing solutions to hard chemical engineering problems

Gavin Jones is a leading quantum chemist and manager in the IBM Quantum Computational Science group, as well as an IBM Quantum Technical Ambassador. In his research, Jones explores chemistry with quantum computers, such as the formation of functional advanced materials, catalysis, molecular properties, and polymer degradation.

Jones brought this expertise to a recent case study with JSR , one of the leading global manufacturers of photoresists — crucial chemical solutions for microchip production worldwide. These solutions are expensive and time-consuming to develop, and the chemistry involved is too complex for even the most powerful classical supercomputers to accurately simulate. Research suggests that quantum computers could help remove barriers of complexity and streamline this process.

Together with JSR, Jones and his team have already shown that quantum computers can simulate small molecules that mimic parts of a photoresist. We met to discuss his own background, the significance of the JSR work, and what it is that makes chemistry “quantum.”

Gavin Jones is a leading quantum chemist and manager in the IBM Quantum Computational Science group, as well as an IBM Quantum Technical Ambassador.

I've heard that “chemistry is quantum.” What does that mean — and why is that relevant to quantum computing?

It means that, at an atomic level, molecules behave according to quantum mechanical principles. Some examples of this are that the particles that make up these molecules (for example, electrons) sometimes act like waves spread out in space. But if the object interacts in specific ways with other particles, it loses its wave-like properties and starts acting like a discrete point — like a particle.

You can also use an equation like the Schrödinger equation — which governs the wave function for a quantum mechanical system — to predict the behavior of a chemical system. For example, you can predict energies of molecules and their properties. You can also do useful tasks such as predicting the likely outcomes of chemical reactions.

You just co-authored a paper with JSR Corporation that “simulated a molecule with similar behaviors to a PAG.” What are PAGs, and what do we gain from efforts to simulate them accurately?

IBM researchers are racing to create more sustainable PAGs, turning to AI to help create them, faster, paving the way to the era of Accelerated Discovery. Read more . PAGs are photo acid generators. These are important molecules in industrial applications such as photolithography or photopolymerization. In photolithography, for example, researchers use light to pattern thin films of polymers over some type of substrate, such as a silicon wafer, to protect selected areas of it during subsequent etching, deposition, or implantation steps. The photoresist either breaks down or hardens where it is exposed to light. The patterned film is then created by removing the softer parts of the coating with appropriate solvents. We require this process for creating microchips.

What is special or new about what you and your collaborators have accomplished with this new paper? Where do you hope to go next?

In my opinion, this is the most advanced chemical simulation done on a quantum computer to date. It’s one of the largest systems that has ever been simulated, and the type of simulation that we’ve done is more complex than anything that has ever been done before. As a proof of concept, this was one of the most ambitious things that has come out in recent chemistry literature.

But we still need to scale up. So far, quantum computing research for chemistry has focused on toy problems of maybe three or four atoms. The problems that we are going to be looking at in the very near future will require technologies that will scale to much larger systems. So that’s the focus of the next adventure. We are trying to develop techniques that will let us increase the size of the simulations so we can explore more industrially relevant simulations of battery materials , OLEDs , crystalline materials, biomolecules and so on.

When did you first become interested in chemistry, and what is it about the field that captured your interest? What about quantum computing?

I loved math growing up, and I’ve had an interest in chemistry ever since high school, when I realized that chemistry requires logical reasoning similar to the logic someone would employ in mathematics. I hated to just memorize stuff, and was really attracted to the fact that there is a logic underpinning chemistry. I thought it was cool that someone could employ such logic to figure out how actual reactions work that make interesting and useful materials in the real world. From then on, from high school to post-doc work and now at IBM, that’s been my main interest — especially the theoretical side.

Today, there are actual chemists in the building who rely on some of the things that we predict to actually go into the lab and try stuff, who then come out and say “oh, based on your predictions, this is what we’ve made.” I find that absolutely amazing and it makes for an exciting work environment.

As for quantum computing, I only started learning about it maybe eight years ago. I heard about it from a senior manager at the time who mentioned its potential for quantum chemistry. As a computational chemist I have always wished for a technique that could provide more accurate predictions than predictions I can obtain on a classical computer. So when I heard that quantum computers could potentially help us to achieve this goal, I became intensely interested and wanted to jump on the bandwagon. I eventually did and I haven’t looked back.

Today, I manage a team of researchers that I'm very happy to support as we work to bring quantum computing to life. I’m hopeful that together with IBM Quantum , my team can use quantum to retrieve more accurate answers and produce more accurate simulations for chemistry.

If you could go back in time and talk to yourself as a young undergraduate chemistry student, what advice would you give him?

I think when you’re an undergraduate and even in high school you naturally have some anxiety for your future. But I think that if you have certain tools, or a certain mindset, it gets you very far. I’d tell myself (or anyone in that position): Don’t stop being curious and don’t stop seeking out new opportunities.

As I mentioned previously, I had no idea about quantum computing until fairly recently. After I heard about it, I wanted to find out as much as possible about the capabilities. I was excited that I had the chance to learn something new and figure out how I could contribute to the field. No matter what your interests are, you should be able to say “I’m curious. I want to learn more. I want to know as much as possible.” If you’re interested — then go after it.


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